1. Field of Invention
This invention relates to a sensing and communicating device, specifically to a miniature device for determining location and survivability of a person under a disaster situation.
2. Description of Prior Art
A person may encounter many different dangerous situations during his or her life. For example, a person may be trapped under a mound of debris created by a fallen building during an earthquake or a terrorist attack. A rescue team is sent to fallen building to search for survivors. It is important for the rescue team to identify the location and status of the trapped person to save the person's life effectively. Although a mobile phone is becoming a popular handheld device, it may not be an effective communication device under a disaster situation. For example, the communication network may be destroyed during an earthquake. Further, a rescue task may take more than 1-2 weeks for a disaster such as an earthquake. The battery of the mobile phone may run out of power in a couple of days for most of devices.
Therefore, it is desirable to have a device carried by a person, which can be used in an emergency situation to communicate with an external rescue station operated by a rescue team. The device should be tiny in its form factor and therefore it can be embedded in the person's clothes or accessories without notification of the person in a normal daily life. The device should also be operated under an extremely low power consumption mode and therefore it is not necessary to replace its power supply or the device itself during a reasonable long operation lifetime of the device.